“Horseshoe crabs are a keystone species for the Delaware Bay. They are critical to the survival of migrating shorebirds. In spring, these living fossils come ashore to lay eggs — just as they have done for the past 445 million years. At the same time, migrating shorebirds arrive thin and exhausted. The Delaware Bay is a stopover for many species, such as the red knot, who consume the energy-rich horseshoe crab eggs while recuperating from their long journeys. A bird can double its weight in just three weeks!
"Behind the scenes, the Bird House team is currently caring for two male and seven female adult horseshoe crabs. The trick to telling them apart is to look at their size and their appendages. Females are larger, and males have specialized claws that allow them to grasp the females during breeding. Since taking these arthropods under our care this summer, I was surprised to learn what curious creatures they are. The crabs spend much of their time investigating novel items and foods that we put in their tanks. They also seem to have distinct personalities! We look forward to introducing the horseshoe crabs to visitors when the Bird House reopens in 2021.” —Sara Hallager, curator
This story appears in the November 2019 issue of National Zoo News. While the Bird House is under construction, Zoo visitors can see birds at Amazonia, American Trail, Cheetah Conservation Station, Kids’ Farm and Small Mammal House.